According to a frantic thread on the official Gears of War forums there is a bug in Gears of War 3 that can end your Gears experience with a single blow and Epic seem at a loss to find the cause.
The issue is that some profiles are being blocked from playing Gears of War 3, this is not to say the game freezes and you have to reboot which is annoying but workable. No this bug stops your profile from playing Gears of War 3 ever again.
Check this video to see someone not being able to play with their profile but once he signs in with his brother’s profile it starts working again.
From what I can see on the official forums it seems to be linked to playing split screen with a vast majority of affected gamers having it first freeze while playing via split screen.
The big problem however is that Epic don’t know how to fix this just yet so we recommend not playing split screen if at all possible until the problem is resolved.
Last Updated: October 11, 2011